Cloth-cutting machine



FEB, :23, 1932.

W. BANGSER CLOTH CUTTING MACHINE Filed Sept. 28, 1929 2 Sheets-Sheet l INVE 33 M, M.MI& Q

,. LLATTORNEYS Feb. 23, 1932. w, BANGSER 1,846,019

7 CLOTH CUTTING MACHINE Filed Sept. 28, 1929 2 Sheets-$heet ZWN/QQMAA/ W f IMH IKF INVE on: L/

ATTORNEYS Patented Feb. 23, 1932 UNITED STATES PATENT OFFICE WILLIAM BANGSEB, OF NEW YORK, N. Y., ASSIGNOR TO B. KLEIN OOIPANY, INCOR- ZPOBATED, A GORPORATION 0F YORK CLOTH-CUTTING MACHINE Application filed September 88, 1929. Serial Io. 385,887.

This invention relates to clothcutting machines of the.reciprocating knife type, and particularly to means for mounting the crossead through which the knife is reciprocated.

Two types of cloth-cutting machines are in common use, the rotary knife type and the reciprocating knife type. The merits of the former are that as long as the knife is rotating and the machine is moved forward throu h the lay the knife is cutting. It is theref bre a more eflicient type of cutter than the reciprocating knife type in which only the down stroke is the effective cutting stroke. On the other hand, the rotary knife cannot be used on relatively thick lays, nor can it be used in cutting very intricate patterns. For such use the reciprocating knife type cutter mustbe employed.

In a cloth-cutting machine of the reciproeating knife type the cutting knife is mounted for vertical reciprocation within an upright standard. The n per end of the knife is fixed to a cross-head w ich is reciprocated in suitable gibs by means of a pitman connected to a crank disc mounted upon the shaft of an electric motor. In machines of this type in use today the cross-liead makes a sliding metal to metal contact with the gibs. Now, for most efficient cutting an extremely rapid rate of reciprocation is required, the motors of the present high speed machines operating at about 3600 R. P. M. Compared with the machines of the rotar knife type, it is necessary that machines 0 the reciprocating type develop greater power. This is because of.

the reater thickness of the lays out, and also because of the sharp corners which it is necessary to turn with these machines. For this reason there is a constant pressure brought to bear on manufacturers of clothcutting machines to build more powerful machines. This might be done by increasing.v

the motor size, but it is practically impossible to do this because of the physical limitations of the machine. It is awkward for an operator to handle a machine upon which a very large and powerful motor is mounted.

In order to permit the development of speeds as high as 3600 R. P. M. when using the sliding cross-head of the present day machine, it is necessary that the cross-head and gib be lubricated continually. At least once an hour the operator must see to it that these parts are well lubricated; if he fails" in this the cross-head will bind and actually stop the machine. It is evident, therefore, that the cross-head and. its mounting constitute an inefficient link in the power chain, and consume wer in overcoming friction which might e applied to better advantage in cutting cloth. 1 7

Another objection to the presenttype of cross-head and gibs arises from the'frequent lubrication required. Even thoughthe operator exercises the utmost care some of the oil escapes at the lower end. of the gibs. and creeps down the standard, ultimately coming in contact with the goods. When working on ,fine fabrics, such as silks, this is .very objectionable and may resultin ruining, if not seriously damaging, the material being cut. i

It is, therefore,the object of the present invention to provide a reciprocating cross-head with its gibs or guideways so constructed as to avoid or minimize the disadvantages discussed above. I have attained this object by interposing bearing balls between the crosshead and the gibs so that instead of a sliding metal to metal contact, I have a rolling metal to metal contact which reduces friction to the minimum and enables me to obtain a substantial increase in power without increasing the size or design of the motor. Such a rolling contact also permits the development of much higher speeds. I can, without difii culty. employ a motor designed to rotate at 4000 R. P. M. and even higher.

By the use of my improved cross-head construction lubrication diiiicultiesare prac- ...11i,c.ally eliminated. Instead of lubricating 9 transverse section taken along line 4-4 of QFigure 1; Figure 5 is a vertical section taken along'line 5-5 of Figure 3: Figure 6 1s a balls roll on each. Each ball, therefore, moves only'one-half the strokeof the cross-I head. Thus, it is necessary for me to'employ a row of balls substantially one-half only the length of the cross-head. The use of more than this number wouldbe objectionable,

because then the end balls. at least during part 9f the stroke, would be sliding and not rollin lustrated a preferred embodiment of my invention, a study of which will make the prin-.

ciples involved clear. In'these drawings Figurel is an end view of a cloth-cutting machine of thereciprocating knife type constructed in accordance with the present invention with the front covei' plate and presser foot: removed to expose the cross-head and gibs; Figure 2 is a longitudinal section taken along line 2 2 of Figure 1 showing the front plate and presser foot in position; Figure 3 is an enlarged transverse section taken along line 33 of Figure 1; Flgure 4 1s a similar I. view similar to Figure 5. but showing a modified construction, and Figure 7 is a transverse section taken along line 7-7 of Figure 6.

The cloth-cutting machine illustrated in these drawings comprises a base 1 from which arises a standard 2, supporting a motor housing 3, a motor 4. and a handle 5. The stand ard 2 and the housing 3 constitute a support for the other parts of the machine. Slidably mounted within a slotted recess in the standard 2 is the cutting knife 6 which is reciprocated by means of the motor through connections which will be described in detail presently. The front of the motor housing 3 is enclosed by means of a plate 8 which carries an adjustable presser foot 9.

The upper end of the knife 6 is bolted to a lug 11 depending from and integral with a cross-head 12. Projecting outwardly from the center of the front face of the cross-head and integral therewithis a boss 13 which [serves as a wrist pin. In order to assist in I keeping the parts cool and to lighten the reing 16. The upper end of this pitinan is fixed to a crankpin 17 journalled within a In the accompanying draw ngs I have 11-;

.posed between the cross-head and the gibs are two series of balls 24 one on either side of the cross-head. I shall now describe the 'manner in which these balls are mounted with particular reference to Figures 3 and 5. The cross-head is provided with a pair of vertical'V-shaped grooves 25, one on either side, these grooves correspondin with and facing similar grooves 26 in the g1 s. These two pairs of opposing grooves constitute races for the balls. The grooves 26 in the gibs may be 0 en at their ends; the grooves in the cross-head, however, are closed, at their lower ends by means of projections 28 on the cross-head, and at their upper ends by means of a removable plate 29; projections 28 and plate 29 serving as stops limiting the movement of the balls. It will be noted from an inspection. of Figure 5 that five balls are employed in each race and that the total overall length of these balls, when tangent, is only slightly greater than one-half the length of the cross-head. It will also be notedithat the cross-head is substantially one-half the length of the gibs. The important feature, however, is the relation between the length of the space through which the balls can freely roll and the length of the cross-head stroke. Thus the throw of the crank disc is such that the stroke of the cross-head is not more than twice the distance between the center of the uppermost ball and the plate 29, as illustrated in Figure 5, with the cross=head in its uppermost position. As a result of this arrangement the balls are moved in rolling relation to both the cross-head and the gibs, each ball moving just one-half the stroke of the cross-head and at neither end of the stroke are these balls, or any of them, slid with reference to the gibs.

In order to supply the necessary small amount of grease to lubricate the balls and their races, I have mounted grease cups 31 on either side of the supporting frame. Each of these grease cups is provided with the usual screw threaded plunger having at its outer end a knurled wheel 32 by the turning of which grease is extruded through the nozzle of the cup. The nozzles of these cups register with opening 33 extending through the middle of the gibs, thus permitting the introduction of grease to the races.

In order to take up wear, one of the gibs is mounted for lateral ncljnsinn-nt upon pins 34-. and moved inward, when occasion arlses, by means of setscrews 35.

In Figures 6 and 7 I have illustrated a,

slightly niollitiecl construction. Here the halls, ineteml of rolling freely in the races, are held in fixed relation to one another by HIL'RDS 0t :1 cage 37. By means of this con- Stlut'lllfill the insertion and removal of the halls from the races is facilitated, but the principles involved are, of course, the same.

B means of the improved cross-head and the gih construction of the present invention 1 am enabled to do away with theolrl sliding cross-head and its attendant clisadvanurges. The rolling contact between the crosshoacl and its gihs materially reduces frietion, enables the use of higher speed motors and permits the effective application of greater power with the same motor. In udilition to theee advantages I have reduced lnhricnting: (.litlicnlties practically to n viinishing point which not only saves the time of the operator, but, in addition, eliminates the neceesity for oil and makes it practically impossible for lubricant to come in Contact with the fabrics heinocut.

when reference is made in this specification and claims to balls I intend, of course, to include rollers and other equivalent antifriction elements.

I claim:

1. In a t'lotl'i-cutting machine, the COHlblnation of :1 lcni to, a reciprocating crosshenrl Connected thereto, LfiiJfi between which the Prose-head moves and halls interposed hotwoon the cross-hearl and gihs, siiirl balls each lining arranged to Hill upon the erossheatl and gih (lU'IlIlQ reciprocation of the crossheed.

in a cloth-cutting nnirhino oi? the reciprocating knife type, thev oon'ihinntion of :1 knife. :1 orosehem'l room-uteri thereto, gihs hetwcrn whirh the eross-h4 ml moves, oppos ing grooves in the cross-head :mtl gihs forinin; rncee. and balls in the races, the halls heing: so positioned with reference to the crossheml rll'lli ite stroke that they are always in rolling relation to the cross-head nncl g'ih.

3. In a. eloth-cntting machine of the re-' ciprocntingr knife type, the combination of a knife, :1 crose-hcml connected thm'oto, gibs between which the (I()Sfi-ll(i1(l moves. opposing: grooves in the crose-houti and gills forming rot-es. stripe at the enlls of the {grooves in the cross-head. and halls in the rnees occopying: a part only of the space between the stops enabling the balls to roll relative to the races as the CFOSS-l1P1l ls' reciproented.

4. In a cloth-cutting nnirhine of the reeiproeating knife type, the combination of a knife, :1 cross-head connected tl'iereto, gibs between which the cross-hea i moves, opposing grooves in the cross-head and gibs forming races, stops at the ends of the grooves in 

